Fredagskollokvium: Multi-fluid solar chromosphere

Elena Khomenko, Instituto de Astrofísica de Canarias

Bildet kan inneholde: hår, ansikt, øyenbryn, hud, hake.

Elena Khomenko, Instituto de Astrofísica de Canarias. Foto: E. Khomenko

The solar chromosphere is the boundary layer between the interior and exterior of the Sun, routing the origins of the coronal heating. Future large-aperture solar telescopes, such as the 4-meter European Solar Telescope and American DKIST, will have among their primary focus observations of chromospheric magnetic fields. The correct interpretation of solar data requires sophisticated theories. The solar chromosphere is made of strongly stratified, weakly ionised and not completely collisionally coupled plasma. The importance of the presence of neutral gas in chromospheric plasma has not been considered to its full extent in the past in the solar physics community. Only now, with the powerful computing techniques that are accessible, we start to be in the position to simulate complex partial ionisation effects and understand their profound consequences. In the recent few years it has been repeatedly demonstrated that processes related to the non-ideal plasma behaviour due to neutrals may be the key ones to solve the problem of chromospheric heating, dynamics and fine structure. In this talk I will describe recent advances and future ambition in multi-fluid modelling of the solar chromosphere.

Images of the solar photosphere and the chromosphere taken by the Swedish Solar Telescope (Roque de los Muchachos Observatory, La Palma). Photosphere is in thermodynamic equilibrium, which feels as a warm day on the beach where a pleasant breeze runs. The chromosphere, is not in thermodynamic or radiative equilibrium and its plasma and radiation are at different temperatures, such as a sunny day on a snowy mountain with a cold wind.


Publisert 23. mai 2019 14:22 - Sist endret 18. des. 2019 11:16